Panel-mountable fiber optic cable feedthrough

Abstract

A novel panel-mountable fiber optic cable feedthrough is described that has two main body parts that can be brought together around a fiber optic cable and secured in place to prevent slippage of the cable. Use of two such main body parts that split along a plane that passes through the axis of the fiber optic cable allows joining the two main parts at any position along the cable without the need to thread the cable through a pre-formed cylindrical cavity in the body of the feedthrough. The main parts for this fiber optic feedthrough can be made by plastic injection molding suitably shaped to relieve bending strain in the glass optical fiber(s) within the cable. The foot-print for mounting such a feedthrough can be made compatible with that of a number of popular fiber optic connector mounts, including the SC-connector.

I claim: 
     
       1. A panel-mountable fiber optic cable feedthrough that is comprised of two main body parts made from a plastic material and each including an open semicircular channel and a flange such that (1) when these parts are assembled around a fiber optic cable and joined together by a mechanical securing means the two semicircular channels in the said main body parts from a full circular cavity around a fiber optic cable with a tight fit having a minimum or zero clearance gap between the outside diameter of the fiber optic cable and the inside diameter of circular cavity in the feedthrough, (2) there are multiple ribs on the inner surface of the circular cavity from 0.1 to 2.0 mm in height that bite down on the outer surface of the fiber optic cable to hold it securely in place when the feedthrough is assembled around the said fiber optic cable, (3) each flange includes at least one penetrating hole so that the feedthrough can be positioned with the holes in the two flanges co-axial and adjacent to similar penetrating holes in an equipment panel and secured to the panel by fasteners, including screws that fit into threaded holes in the equipment panel or with matching nuts if the screws pass entirely through the equipment panel, and (4) one or both ends of the circular cavity have a trumpet bell-shaped flare with a minimum radius of curvature of 3 mm to provide strain relief for the optical fibers(s) in the fiber optic cable. 
     
     
       2. A panel-mountable fiber optic feedthrough as in  claim 1  having the two main body parts made of plastic materials comprised of nylon, poly-acrylate, high density polyethylene (HDPE), or polyurethane. 
     
     
       3. A panel-mountable fiber optic feedthrough as in  claim 1  having its two main body parts interconnected by a thin flexible strip of plastic that is injection molded simultaneously with the two main body parts and that serves as a hinge when the these body parts are rotated closed around a fiber optic cable. 
     
     
       4. A panel-mountable fiber optic feedthrough as in  claim 1  with each of its two main body parts having two latching arms that secure to the other body part when joined together around a fiber optic cable. 
     
     
       5. A panel-mountable fiber optic feedthrough as in  claim 1  having its two main body parts secured together with two screws sufficiently off-set from the centerline of the feedthrough body so that the circular cavity is not penetrated by the screws. 
     
     
       6. A panel-mountable fiber optic feedthrough as in  claim 1  in which the two main body parts are secured together by a “U” shaped spring clip having detents at both ends that come to rest in surface channels, one on each of the main body parts. 
     
     
       7. A panel-mountable fiber optic cable feedthrough that is composed of two main body parts made of plastic each including an open semicircular channel with a series of ribs spaced along the length of the semi-circular channel and a flange such that (1) when these parts are brought together around a fiber optic cable and joined together by a mechanical securing means the two semicircular channels in the said main body parts from a full circular cavity around a fiber optic cable with a tight fit having a minimum or zero clearance gap between the outside diameter of the fiber optic cable and the inside diameter of circular cavity in the feedthrough, and (2) each flange includes at least one penetrating hole so that the feedthrough can be positioned with the holes in the two flanges co-axial and adjacent to similar penetrating holes in an equipment panel and secured to the panel by fasteners, including screws that fit into threaded holes in the equipment panel or with optional matching nuts if the screws pass entirely through the equipment panel, (3) one or both of the ends of the circular cavity have a trumpet bell-shaped flare to provide strain relief for the optical fiber(s) in the fiber optic cable. 
     
     
       8. A panel-mountable fiber optic cable feedthrough that is composed of two main body parts made of plastic and each including an open semicircular channel with a series of ribs spaced along the length of the semi-circular channel and a flange such that (1) when these parts are brought together around a fiber optic cable and joined together by a mechanical securing means consisting of one of the following alternatives:
 (a) a plastic hinge between the two main body parts with two latching arms attach to one of the main body parts that fit into two channels in the other main body part, 
 (b) four latching arms, two in one of the main body parts and two more in the other main body part that facilitate snapping these body parts together, 
 (c) two screws that secure the two main body parts together, or 
 (d) a “U” shaped spring clip with detents on each end that slides in place over the two main body parts and the spring's detents fall into channels in each of the main body parts 
 
       the two semicircular channels in the said main body parts from a full circular cavity around a fiber optic cable with a sufficiently tight fit that the fiber optic cable is tightly held in place relative to the feedthrough and (2) each flange includes at least one penetrating hole so that the feedthrough can be positioned with the holes in the two flanges co-axial and adjacent to similar penetrating holes in an equipment panel and secured to the panel by fasteners, including screws that fit into threaded holes in the equipment panel or with optional nuts if the screws pass entirely through the equipment panel, (3) one or both of the ends of the circular cavity have a trumpet-bell shaped flare to provide strain relief for the optical fibers in the fiber optic cable.